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1   ///////////////////////////////////////////////////////////////////////////////////////////////
2   // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3   // Copyright (C) 2001-2024 the original author or authors.
4   //
5   // This library is free software; you can redistribute it and/or
6   // modify it under the terms of the GNU Lesser General Public
7   // License as published by the Free Software Foundation; either
8   // version 2.1 of the License, or (at your option) any later version.
9   //
10  // This library is distributed in the hope that it will be useful,
11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  // Lesser General Public License for more details.
14  //
15  // You should have received a copy of the GNU Lesser General Public
16  // License along with this library; if not, write to the Free Software
17  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  ///////////////////////////////////////////////////////////////////////////////////////////////
19  
20  package com.puppycrawl.tools.checkstyle;
21  
22  import java.beans.PropertyDescriptor;
23  import java.lang.reflect.InvocationTargetException;
24  import java.net.URI;
25  import java.util.ArrayList;
26  import java.util.Collection;
27  import java.util.List;
28  import java.util.Locale;
29  import java.util.StringTokenizer;
30  import java.util.regex.Pattern;
31  
32  import javax.annotation.Nullable;
33  
34  import org.apache.commons.beanutils.BeanUtilsBean;
35  import org.apache.commons.beanutils.ConversionException;
36  import org.apache.commons.beanutils.ConvertUtilsBean;
37  import org.apache.commons.beanutils.Converter;
38  import org.apache.commons.beanutils.PropertyUtils;
39  import org.apache.commons.beanutils.PropertyUtilsBean;
40  import org.apache.commons.beanutils.converters.ArrayConverter;
41  import org.apache.commons.beanutils.converters.BooleanConverter;
42  import org.apache.commons.beanutils.converters.ByteConverter;
43  import org.apache.commons.beanutils.converters.CharacterConverter;
44  import org.apache.commons.beanutils.converters.DoubleConverter;
45  import org.apache.commons.beanutils.converters.FloatConverter;
46  import org.apache.commons.beanutils.converters.IntegerConverter;
47  import org.apache.commons.beanutils.converters.LongConverter;
48  import org.apache.commons.beanutils.converters.ShortConverter;
49  
50  import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
51  import com.puppycrawl.tools.checkstyle.api.Configurable;
52  import com.puppycrawl.tools.checkstyle.api.Configuration;
53  import com.puppycrawl.tools.checkstyle.api.Context;
54  import com.puppycrawl.tools.checkstyle.api.Contextualizable;
55  import com.puppycrawl.tools.checkstyle.api.Scope;
56  import com.puppycrawl.tools.checkstyle.api.SeverityLevel;
57  import com.puppycrawl.tools.checkstyle.checks.naming.AccessModifierOption;
58  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
59  
60  /**
61   * A Java Bean that implements the component lifecycle interfaces by
62   * calling the bean's setters for all configuration attributes.
63   */
64  public abstract class AbstractAutomaticBean
65      implements Configurable, Contextualizable {
66  
67      /**
68       * Enum to specify behaviour regarding ignored modules.
69       */
70      public enum OutputStreamOptions {
71  
72          /**
73           * Close stream in the end.
74           */
75          CLOSE,
76  
77          /**
78           * Do nothing in the end.
79           */
80          NONE,
81  
82      }
83  
84      /** Comma separator for StringTokenizer. */
85      private static final String COMMA_SEPARATOR = ",";
86  
87      /** The configuration of this bean. */
88      private Configuration configuration;
89  
90      /**
91       * Provides a hook to finish the part of this component's setup that
92       * was not handled by the bean introspection.
93       * <p>
94       * The default implementation does nothing.
95       * </p>
96       *
97       * @throws CheckstyleException if there is a configuration error.
98       */
99      protected abstract void finishLocalSetup() throws CheckstyleException;
100 
101     /**
102      * Creates a BeanUtilsBean that is configured to use
103      * type converters that throw a ConversionException
104      * instead of using the default value when something
105      * goes wrong.
106      *
107      * @return a configured BeanUtilsBean
108      */
109     private static BeanUtilsBean createBeanUtilsBean() {
110         final ConvertUtilsBean cub = new ConvertUtilsBean();
111 
112         registerIntegralTypes(cub);
113         registerCustomTypes(cub);
114 
115         return new BeanUtilsBean(cub, new PropertyUtilsBean());
116     }
117 
118     /**
119      * Register basic types of JDK like boolean, int, and String to use with BeanUtils. All these
120      * types are found in the {@code java.lang} package.
121      *
122      * @param cub
123      *            Instance of {@link ConvertUtilsBean} to register types with.
124      */
125     private static void registerIntegralTypes(ConvertUtilsBean cub) {
126         cub.register(new BooleanConverter(), Boolean.TYPE);
127         cub.register(new BooleanConverter(), Boolean.class);
128         cub.register(new ArrayConverter(
129             boolean[].class, new BooleanConverter()), boolean[].class);
130         cub.register(new ByteConverter(), Byte.TYPE);
131         cub.register(new ByteConverter(), Byte.class);
132         cub.register(new ArrayConverter(byte[].class, new ByteConverter()),
133             byte[].class);
134         cub.register(new CharacterConverter(), Character.TYPE);
135         cub.register(new CharacterConverter(), Character.class);
136         cub.register(new ArrayConverter(char[].class, new CharacterConverter()),
137             char[].class);
138         cub.register(new DoubleConverter(), Double.TYPE);
139         cub.register(new DoubleConverter(), Double.class);
140         cub.register(new ArrayConverter(double[].class, new DoubleConverter()),
141             double[].class);
142         cub.register(new FloatConverter(), Float.TYPE);
143         cub.register(new FloatConverter(), Float.class);
144         cub.register(new ArrayConverter(float[].class, new FloatConverter()),
145             float[].class);
146         cub.register(new IntegerConverter(), Integer.TYPE);
147         cub.register(new IntegerConverter(), Integer.class);
148         cub.register(new ArrayConverter(int[].class, new IntegerConverter()),
149             int[].class);
150         cub.register(new LongConverter(), Long.TYPE);
151         cub.register(new LongConverter(), Long.class);
152         cub.register(new ArrayConverter(long[].class, new LongConverter()),
153             long[].class);
154         cub.register(new ShortConverter(), Short.TYPE);
155         cub.register(new ShortConverter(), Short.class);
156         cub.register(new ArrayConverter(short[].class, new ShortConverter()),
157             short[].class);
158         cub.register(new RelaxedStringArrayConverter(), String[].class);
159 
160         // BigDecimal, BigInteger, Class, Date, String, Time, TimeStamp
161         // do not use defaults in the default configuration of ConvertUtilsBean
162     }
163 
164     /**
165      * Register custom types of JDK like URI and Checkstyle specific classes to use with BeanUtils.
166      * None of these types should be found in the {@code java.lang} package.
167      *
168      * @param cub
169      *            Instance of {@link ConvertUtilsBean} to register types with.
170      */
171     private static void registerCustomTypes(ConvertUtilsBean cub) {
172         cub.register(new PatternConverter(), Pattern.class);
173         cub.register(new PatternArrayConverter(), Pattern[].class);
174         cub.register(new SeverityLevelConverter(), SeverityLevel.class);
175         cub.register(new ScopeConverter(), Scope.class);
176         cub.register(new UriConverter(), URI.class);
177         cub.register(new RelaxedAccessModifierArrayConverter(), AccessModifierOption[].class);
178     }
179 
180     /**
181      * Implements the Configurable interface using bean introspection.
182      *
183      * <p>Subclasses are allowed to add behaviour. After the bean
184      * based setup has completed first the method
185      * {@link #finishLocalSetup finishLocalSetup}
186      * is called to allow completion of the bean's local setup,
187      * after that the method {@link #setupChild setupChild}
188      * is called for each {@link Configuration#getChildren child Configuration}
189      * of {@code configuration}.
190      *
191      * @see Configurable
192      */
193     @Override
194     public final void configure(Configuration config)
195             throws CheckstyleException {
196         configuration = config;
197 
198         final String[] attributes = config.getPropertyNames();
199 
200         for (final String key : attributes) {
201             final String value = config.getProperty(key);
202 
203             tryCopyProperty(key, value, true);
204         }
205 
206         finishLocalSetup();
207 
208         final Configuration[] childConfigs = config.getChildren();
209         for (final Configuration childConfig : childConfigs) {
210             setupChild(childConfig);
211         }
212     }
213 
214     /**
215      * Recheck property and try to copy it.
216      *
217      * @param key key of value
218      * @param value value
219      * @param recheck whether to check for property existence before copy
220      * @throws CheckstyleException when property defined incorrectly
221      */
222     private void tryCopyProperty(String key, Object value, boolean recheck)
223             throws CheckstyleException {
224         final BeanUtilsBean beanUtils = createBeanUtilsBean();
225 
226         try {
227             if (recheck) {
228                 // BeanUtilsBean.copyProperties silently ignores missing setters
229                 // for key, so we have to go through great lengths here to
230                 // figure out if the bean property really exists.
231                 final PropertyDescriptor descriptor =
232                         PropertyUtils.getPropertyDescriptor(this, key);
233                 if (descriptor == null) {
234                     final String message = String.format(Locale.ROOT, "Property '%s' "
235                             + "does not exist, please check the documentation", key);
236                     throw new CheckstyleException(message);
237                 }
238             }
239             // finally we can set the bean property
240             beanUtils.copyProperty(this, key, value);
241         }
242         catch (final InvocationTargetException | IllegalAccessException
243                 | NoSuchMethodException ex) {
244             // There is no way to catch IllegalAccessException | NoSuchMethodException
245             // as we do PropertyUtils.getPropertyDescriptor before beanUtils.copyProperty,
246             // so we have to join these exceptions with InvocationTargetException
247             // to satisfy UTs coverage
248             final String message = String.format(Locale.ROOT,
249                     "Cannot set property '%s' to '%s'", key, value);
250             throw new CheckstyleException(message, ex);
251         }
252         catch (final IllegalArgumentException | ConversionException ex) {
253             final String message = String.format(Locale.ROOT, "illegal value '%s' for property "
254                     + "'%s'", value, key);
255             throw new CheckstyleException(message, ex);
256         }
257     }
258 
259     /**
260      * Implements the Contextualizable interface using bean introspection.
261      *
262      * @see Contextualizable
263      */
264     @Override
265     public final void contextualize(Context context)
266             throws CheckstyleException {
267         final Collection<String> attributes = context.getAttributeNames();
268 
269         for (final String key : attributes) {
270             final Object value = context.get(key);
271 
272             tryCopyProperty(key, value, false);
273         }
274     }
275 
276     /**
277      * Returns the configuration that was used to configure this component.
278      *
279      * @return the configuration that was used to configure this component.
280      */
281     protected final Configuration getConfiguration() {
282         return configuration;
283     }
284 
285     /**
286      * Called by configure() for every child of this component's Configuration.
287      * <p>
288      * The default implementation throws {@link CheckstyleException} if
289      * {@code childConf} is {@code null} because it doesn't support children. It
290      * must be overridden to validate and support children that are wanted.
291      * </p>
292      *
293      * @param childConf a child of this component's Configuration
294      * @throws CheckstyleException if there is a configuration error.
295      * @see Configuration#getChildren
296      */
297     protected void setupChild(Configuration childConf)
298             throws CheckstyleException {
299         if (childConf != null) {
300             throw new CheckstyleException(childConf.getName() + " is not allowed as a child in "
301                     + configuration.getName() + ". Please review 'Parent Module' section "
302                     + "for this Check in web documentation if Check is standard.");
303         }
304     }
305 
306     /** A converter that converts a string to a pattern. */
307     private static final class PatternConverter implements Converter {
308 
309         @SuppressWarnings("unchecked")
310         @Override
311         public Object convert(Class type, Object value) {
312             return CommonUtil.createPattern(value.toString());
313         }
314 
315     }
316 
317     /** A converter that converts a comma-separated string into an array of patterns. */
318     private static final class PatternArrayConverter implements Converter {
319 
320         @SuppressWarnings("unchecked")
321         @Override
322         public Object convert(Class type, Object value) {
323             final StringTokenizer tokenizer = new StringTokenizer(
324                     value.toString(), COMMA_SEPARATOR);
325             final List<Pattern> result = new ArrayList<>();
326 
327             while (tokenizer.hasMoreTokens()) {
328                 final String token = tokenizer.nextToken();
329                 result.add(CommonUtil.createPattern(token.trim()));
330             }
331 
332             return result.toArray(new Pattern[0]);
333         }
334     }
335 
336     /** A converter that converts strings to severity level. */
337     private static final class SeverityLevelConverter implements Converter {
338 
339         @SuppressWarnings("unchecked")
340         @Override
341         public Object convert(Class type, Object value) {
342             return SeverityLevel.getInstance(value.toString());
343         }
344 
345     }
346 
347     /** A converter that converts strings to scope. */
348     private static final class ScopeConverter implements Converter {
349 
350         @SuppressWarnings("unchecked")
351         @Override
352         public Object convert(Class type, Object value) {
353             return Scope.getInstance(value.toString());
354         }
355 
356     }
357 
358     /** A converter that converts strings to uri. */
359     private static final class UriConverter implements Converter {
360 
361         @SuppressWarnings("unchecked")
362         @Override
363         @Nullable
364         public Object convert(Class type, Object value) {
365             final String url = value.toString();
366             URI result = null;
367 
368             if (!CommonUtil.isBlank(url)) {
369                 try {
370                     result = CommonUtil.getUriByFilename(url);
371                 }
372                 catch (CheckstyleException ex) {
373                     throw new IllegalArgumentException(ex);
374                 }
375             }
376 
377             return result;
378         }
379 
380     }
381 
382     /**
383      * A converter that does not care whether the array elements contain String
384      * characters like '*' or '_'. The normal ArrayConverter class has problems
385      * with these characters.
386      */
387     private static final class RelaxedStringArrayConverter implements Converter {
388 
389         @SuppressWarnings("unchecked")
390         @Override
391         public Object convert(Class type, Object value) {
392             final StringTokenizer tokenizer = new StringTokenizer(
393                 value.toString().trim(), COMMA_SEPARATOR);
394             final List<String> result = new ArrayList<>();
395 
396             while (tokenizer.hasMoreTokens()) {
397                 final String token = tokenizer.nextToken();
398                 result.add(token.trim());
399             }
400 
401             return result.toArray(CommonUtil.EMPTY_STRING_ARRAY);
402         }
403 
404     }
405 
406     /**
407      * A converter that converts strings to {@link AccessModifierOption}.
408      * This implementation does not care whether the array elements contain characters like '_'.
409      * The normal {@link ArrayConverter} class has problems with this character.
410      */
411     private static final class RelaxedAccessModifierArrayConverter implements Converter {
412 
413         /** Constant for optimization. */
414         private static final AccessModifierOption[] EMPTY_MODIFIER_ARRAY =
415                 new AccessModifierOption[0];
416 
417         @SuppressWarnings("unchecked")
418         @Override
419         public Object convert(Class type, Object value) {
420             // Converts to a String and trims it for the tokenizer.
421             final StringTokenizer tokenizer = new StringTokenizer(
422                 value.toString().trim(), COMMA_SEPARATOR);
423             final List<AccessModifierOption> result = new ArrayList<>();
424 
425             while (tokenizer.hasMoreTokens()) {
426                 final String token = tokenizer.nextToken();
427                 result.add(AccessModifierOption.getInstance(token));
428             }
429 
430             return result.toArray(EMPTY_MODIFIER_ARRAY);
431         }
432 
433     }
434 
435 }